Hookworms are small, thin nematodes that are approximately 1/4 to 1/2 in length. They are a common intestinal parasitic worm of dogs, and less so in cats.
Hookworms live in the small intestine of the cat, attaching themselves to the intestinal wall using teeth like mouth parts (see photo) where they feed on the blood and tissue. This blood loss can lead to anaemia, intestinal bleeding, intestinal inflammation, diarrhea and even death.
There are several types of hookworms to infect cats:
There are a number of ways cats can become infected with hookworms and it is important to understand the life cycle of hookworms, which will be explained below.
- Via the skin: Hookworm eggs are passed in the cat's stool. Depending on conditions, within 2 - 5 days these eggs hatch into larvae (immature worms), which are present in the moist environment of soil, and vegetation. When a cat comes into contact with an environment infected with hookworm larvae, it either becomes infected via ingestion of the larvae, or they enter the body by burrowing into the skin.
- Via ingestion: Hookworm larvae can contaminate food and water which the cat consumes.
- In utero: Worm eggs may be passed on from mother to her unborn puppies via the placenta. It hasn't been established if this is the case with feline hookworms yet.
- Via the mother's milk: Again, in dogs, it is possible for hookworm infection to be passed to her puppies via the breast milk. When a dog becomes infected with hookworms most of them migrate to the small intestine. However, some enter other tissues of the body, becoming dormant for years. When the animal becomes pregnant, they migrate to the mammary glands and are passed through the milk. It hasn't been established if this is the case with cat hookworms yet.
Adult hookworms live in the small intestine of their host. They lay hundreds of eggs which are passed out in the feces. Within 2 - 5 days these eggs hatch into larvae (immature worms), which are present in soil/environment etc., and are ready to infect a host. The larvae can survive for quite a long time in the environment without a host to feed on.
Ingestion: The cat swallows the comes into contact with the larvae food or water infected with hookworm larvae, these larvae move down into the small intestine.
Penetration: The larvae comes into contact with the cat's skin and burrows into the body. They migrate into the blood and up into the lungs and trachea, where they are coughed up and swallowed.
Some migrating larvae don't move into the small intestine, instead, they encyst in the tissues. In dogs, these larvae are re-activated by pregnancy, but it is not sure if the same happens in cats.
Once in the small intestine, the larvae attach to the wall of the small intestine where they feed and mature. Once they have reached maturity they lay eggs, which are passed out in the faeces.
Symptoms of hookworms vary depending on the severity of infection and the type of hookworm involved. In some cats, no symptoms are apparent. When symptoms do appear, they typically include:
Your veterinarian will be able to diagnose hookworm via fecal flotation. A stool sample from your cat is mixed with a liquid solution, any eggs present in the feces float to the top. These are collected and viewed under a microscope to determine the type (hookworm, roundworm etc) and a number of eggs present.
Hookworms tend to be more prevalent in dogs than they are in cats, and when cats do have them, they are more likely to be in smaller numbers. Any worm infestation should be treated immediately. As hookworms feed on the cat's blood, cats can become anaemic. Adult cats are more resistant to hookworms than kittens.
There are many effective medications to treat hookworms. Your veterinarian will be able to recommend an effective product.
Most worming medications come in two forms, either topical which is applied to the skin on the back of the neck or tablet form.
Severely infected kittens may require hospitalisation and blood transfusions to treat anemia.
This is a debatable topic and veterinarians seem to vary in their opinion. Generally speaking, it is recommended that you worm your cat from time to time (once or twice a year) as it is possible to transport worm eggs into the house via our shoes. Speak to your own veterinarian if you are unsure if you should worm your indoor only cat.
You can, although they can't develop into the adult form as they do in cats. The infective larvae are found in the soil or sandy areas such as beaches or children's sandpits are able to penetrate the skin and they migrate, causing a red, itchy skin eruption. This condition is known as 'Cutaneous Larva Migrans' (also called 'creeping eruption' or 'ground itch'). The hookworm larvae cannot complete their life cycle and die in the epidermis.
Humans are more commonly affected by pinworms, which are a common type of worm found predominantly in school-aged children.
- Regular worming, every three to six months, or as recommended for the particular brand of worming product you are using. All cats in the household should be wormed at the same time.
- Regular cleaning and removal of faecal waste in your cat's litter tray.
- Preventing hunting in cats.
- If you do allow your cat to go to the toilet in your garden, ensure you clean up any feces quickly.
- If you are planning to breed your female cat, she should be de-wormed two weeks prior to breeding and receive another dose late in pregnancy.
- Kittens should be wormed from two weeks of age and then every two weeks until they are 12 weeks old.
Adults and children should avoid walking barefoot in areas which have been defecated in by animals.